176,847 research outputs found
Exclusive diffractive electroproduction of dijets in collinear factorization
Exclusive electroproduction of hard dijets can be described within the
collinear factorization. This process has clear experimental signature and
provides one with an interesting alternative venue to test QCD description of
hard diffractive processes and extract information on generalized nucleon
parton distributions. In this work we present detailed leading-order QCD
calculations of the relevant cross sections, including longitudinal momentum
fraction distribution of the dijets and their azimuthal angle dependence.Comment: 11 pages, 14 Postscript figures, uses revtex4.st
Analysis of clustering phenomena in ab initio approaches
An approach for explicit consideration of cluster effects in nuclear systems
and accurate ab initio calculations of cluster characteristics of nuclei is
devised. The essential block of the approach is a construction of a basis which
incorporates both conventional No-Core Shell Model wave functions and
translationally-invariant wave functions of various cluster channels. The
results of computations of the total binding energies of 8Be nucleus as well as
the spectroscopic factors of cluster channels (amount of clustering) are
presented. An unexpected fresh result of the rigorous study is that the
contribution of "non-clustered" components of the basis to the total binding
energy is great even in the typical cluster systems such as the discussed
nucleus
Description of bulk observables in Au+Au collisions at top RHIC energy in the integrated HydroKinetic Model
The results on the main bulk observables obtained in the simulations within
the integrated hydrokinetic model (iHKM) of Au+Au collisions at the RHIC energy
GeV are presented along with the corresponding experimental
data from the STAR and the PHENIX collaborations. The simulations include all
the stages of the collision process: formation of the initial state, its
gradual thermalization and hydrodynamization, viscous relativistic
hydro-evolution, system's hadronization and particlization, and, finally, an
expansion of the interacting hadron-resonance gas. The model gives a
satisfactory description of charged-particle multiplicities, particle number
ratios, transverse momentum spectra for pions, kaons, protons and antiprotons,
charged-particle coefficients, and femtoscopy radii at all collision
centralities. It is demonstrated how one can estimate the times of the pion and
kaon maximal emission from the femto-scales.Comment: 17 pages, 14 figure
Description of bulk observables in Au+Au collisions at top RHIC energy in the integrated HydroKinetic Model
The results on the main bulk observables obtained in the simulations within
the integrated hydrokinetic model (iHKM) of Au+Au collisions at the RHIC energy
GeV are presented along with the corresponding experimental
data from the STAR and the PHENIX collaborations. The simulations include all
the stages of the collision process: formation of the initial state, its
gradual thermalization and hydrodynamization, viscous relativistic
hydro-evolution, system's hadronization and particlization, and, finally, an
expansion of the interacting hadron-resonance gas. The model gives a
satisfactory description of charged-particle multiplicities, particle number
ratios, transverse momentum spectra for pions, kaons, protons and antiprotons,
charged-particle coefficients, and femtoscopy radii at all collision
centralities. It is demonstrated how one can estimate the times of the pion and
kaon maximal emission from the femto-scales.Comment: 17 pages, 14 figure
New critical behavior in unconventional ferromagnetic superconductors
New critical behavior in unconventional superconductors and superfluids is
established and described by the Wilson-Fisher renormalization-group method.
For certain ordering symmetries a new type of fluctuation-driven first order
phase transitions at finite and zero temperature are predicted. The results can
be applied to a wide class of ferromagnetic superconducting and superfluid
systems, in particular, to itinerant ferromagnets as UGe2 and URhGe.Comment: 12 pages, 6 fig
Gate-controlled superconductivity in diffusive multiwalled carbon nanotube
We have investigated electrical transport in a diffusive multiwalled carbon
nanotube contacted using superconducting leads made of Al/Ti sandwich
structure. We find proximity-induced superconductivity with measured critical
currents up to I_cm = 1.3 nA, tunable by gate voltage down to 10 pA. The
supercurrent branch displays a finite zero bias resistance which varies as R_0
proportional to I_cm^-alpha with alpha=0.74. Using IV-characteristics of
junctions with phase diffusion, a good agreement is obtained with Josephson
coupling energy in the long, diffusive junction model of A.D Zaikin and G.F.
Zharkov (Sov. J. Low Temp. Phys. 7, 184 (1981)).Comment: 5 pages, 4 figure
On the problem of catastrophic relaxation in superfluid 3-He-B
In this Letter we discussed the parametric instability of texture of
homogeneous (in time) spin precession, explaining how spatial inhomogeneity of
the texture may change the threshold of the instability in comparison with
idealized spatial homogeneous case, considered in our JETP Letter \textbf{83},
530 (2006), cond-mat/0605386. This discussion is inspired by critical Comment
of I.A. Fomin (cond-mat/0606760) related to the above questions. In addition we
considered here results of direct numerical simulations of the full
Leggett-Takagi equation of motion for magnetization in superfluid 3He-B and
experimental data for magnetic field dependence of the catastrophic relaxation,
that provide solid support of the theory of this phenomenon, presented in our
2006 JETP Letter.Comment: 5 pages, 1 fig. included, JETP Lett. style, submitted to JETP Lett.
as response to Comment cond-mat/060676
Stripping Cross Sections in Collisions of Light Nuclei
By evaluating all the contributions of the intermediate states of the
multiple scattering theory diagrams, we compute the integrated stripping cross
sections of collisions among light nuclei. The resulting expressions have the
simple form of a combination of total inelastic cross sections of nuclear
reactions with projectile nuclei differing in the atomic mass number. We also
check the accuracy of some widely used relations in heavy ion collisions.Comment: 9 pages, 4 figures, Latex fil
The c-axis charge traveling wave in coupled system of Josephson junctions
We demonstrate a manifestation of the charge traveling wave along the c-axis
(TW) in current voltage characteristics of coupled Josephson junctions in
high- superconductors. The branches related to the TW with different
wavelengths are found for the stacks with different number of Josephson
junctions at different values of system's parameters. Transitions between the
TW branches and the outermost branch are observed. Time dependence of the
electric charge in the superconducting layers and charge-charge correlation
functions for TW and outermost branches show different behavior with bias
current. We propose an experimental testing of the TW by microwave irradiation.Comment: Supplement : http://theor.jinr.ru/~hamdipur/lambda0.av
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